PEROGNATHUS. 



353 



FIG. 67. PEROGNATHUS MERRIAMI. 



No. 4963 Field Columbian Mus. Coll. Twice nat. size 



UPPER TOOTH ROW. LOWER TOOTH ROW. 



Enlarged 10 times. Enlarged 10 times. 



A. Perognathus. 



Mastoids well developed, extending beyond occipital line; inter- 

 parietal pentagonal; mastoid side of parietal longest; audital bullae 

 nearly contiguous below basisphenoid. 



KEY TO THE SPECIES AND SUBSPECIES OF THE SUBGENUS. 



A. Size small; hind foot less than 18 mm. 

 a. Tail about 60 mm. 



a/ Above ochraceous and black P. merriami 



b.' Above pale fulvous or buff and black. 



a." Hind foot, 15 mm P. flavus 



b." Hind foot, 17 mm P. f. mexicanus 



c." Hind foot, 17.4 mm P. p. brevinasus 



c/ Above pale ochraceous drab and black .... P. pacificus 



B. Size large; hind foot over 18 mm P. a. melanotis 



PAGE 



353 



354 

 355 

 355 

 355 

 356 



359. merriami (Perognathus}, Allen, Bull. Am. Mus. Nat. Hist., 

 1892, p. 45, pi. in, figs. 1-6. Elliot, Syn. N. Am. Mamm., 

 1901, p. 243. 

 mearnsi Allen, Bull. Am. Mus. Nat. Hist., 1896, p. 237. 



